Folding machines for laundry use



Oct, 29, 1957 w. B. G. CRAN ET AL 2,311,350

FOLDING MACHINES FOR LAUNDRY USE 4 Sheets-Sheet 1 Filed July 23, 1954I12, 0 617:8015 E4616; Crazz/ 1.4.1reland EILPrzLiaM-rd Z .7, zrecilezOct. 29, 1957 w. B. G. CRAN ETAL 2,811,350

' FOLDING MACHINES FOR LAUNDRY USE Filed July 23, 1954 4 Sheets-Sheet 2a-zzzu'en'om Get. 29, 1957 w, GRAN ET AL 2,811,350

FOLDING MACHINES FOR LAUNDRY USE Filed July 23, 1954 4 Sheets-Sheet 3Oct. 29, 1957 w. B. G. CRAN ET AL 2,811,350

FOLDING MACHINES FOR LAUNDRY USE,

4 Sheets-Sheet 4 Filed July 23, 1954 rornrso MACS ron LAUNDRY USEWilliam Broadbent Gordon Cran, Arthur Ireland, Hubert Keith Spreckley,London, England Application July 23, 1954, Serial No. 445,386

Claims priority, application Great Britain February 1, 1954 8 Claims.(Cl. 270- 68) Huddersfield, and Alec Pritchard, and Frank This inventionrelates to machines for folding towels, pillowcases, sheets and otherflatwork in laundries.

In the conventional type of folding mechanism, the leading edge of thearticle to be folded is lifted by means of a moving plate or bar(hereinafter called moving plate) and nipped against a fixed bar. Onemethod of causing the actuation of the moving plate is for the leadingedge of the article to move in sequence two arms situated in the path ofthe article as it moves along a conveyor. These arms actuate electricalswitching means or compressed air valves. To ensure that the leadingedge of the article reaches the moving plate before this is lifted byits solenoid, compressed air piston or other operating means, the secondarm which causes the actuation of said operating means is positioned ator slightly before the rear edge of the moving plate. When the leadingedge of the article moves the said second arm, and so brings theaforesaid moving plate operating means into action, such plate travelsupwards carrying with it the leading edge of the article. Due tovariations in the articles being folded there is danger of mutualjamming between the fixed bar, the article being folded and the secondarm, either during the pick up or at a later stage when the tail of thearticle passes the arm which actuates means causing the release of theleading edge of the article which should fall clear on to the rear edgeand complete the fold. In both cases there is a possibility of damage tothe second arm, and in the second case there will be a poor fold even ifthe article eventually frees itself.

The object of the present invention is to provide simple and etlicientmeans for obviating the disadvantages above indicated due to mutualjamming between the fixed bar, the article being folded and the secondarm.

The invention consists in a foldng machine comprising in combination, aconveyor for the articles to be folded, a first switch arm engaged firstby the leading edge of each article to be folded, a second switch armengaged secondly by the article to be folded, a moving plate adapted tobe raised by a solenoid when the article has moved both switch arms andholds them in their displaced position when the circuit of the solenoidis closed, characterised in this that the second arm which normallyextends behind and at its bottom end projects forward through a slot inthe moving plate, is supported by a part of said moving plate so thatwhen the latter is raised to grip the leading edge of the articleagainst a fixed bar, the second arm is moved by the moving platebackwards so that its bottom end is clear of the position where thearticle is clipped and so cannot become jammed between the fixed bar andthe moving plate and cannot interfere with the folding of the article.

The invention further comprises a folding machine as aforesaid in whicha catch prevents the final descent of the moving plate until the foldedarticle has passed from under the moving plate.

The invention further comprises a folding machine as aforesaid in whichthe catch is brought into operative posi- 2,81 1,350 Patented Oct. 29,1957 tion to prevent the final descent of the moving plate by 'asolenoid which is energised by current through a switch operated'b'ythearticle being folded.

The invention further comprises a folding machine as aforesaid in whichthe first switch closes thesolenoid circuit when the articlepasse's'frorn beneath the first switch arm, such circuit beingmaintained for a'predete'rmined interval of time during which thearticle passes from beneath the moving plate.

The invention further comprises a folding machine as aforesaid in whichathird arm operated by the folded article beyond the second arm act-uatesa switch in the solenoid circuit to energise the solenoid andcause thecatch to hold up the descent of the moving plate whilst the article isbeneath the third arm. I

Referring to the accompanying explanatory drawings Figures 1, Zand 3arediagrams showing three positions of the parts which control'the grippingof the leading edge of the article which is being folded as it is beingcarried along on-a conveyor, such parts being arranged in onec'onveni'ent form in accordance with this invention.

Figures 4, Sand 6 show three positions of the parts arranged in oneconvenient form in accordance with this invention, which control thedescent'of the moving plate after it has released its grip of theleading edge of the article which is being foldedfl. Y

Figure 7 is .an end view' of the parts shown in Figure 1, looking fromright to left in that figure.

Figure 8 and 9show .a modified arrangement for controlling the descentofthe moving plate after it has released its grip on theleading edge ofthe article which is being folded. Figure 8 shows the moving plategripping the leading edge ofthe article whilst folding proceeds andFigure 9 shows the leading edge of the article which has justbeenreleasedbut the folds are still beneath the moving plate. 11 q 1 FiguresIO-and 11 are views similar to Figures 8 and 9 but showing a furthermodified arrangement for controlling the descent of-the moving plate.

In Figures 1, 2' and 3, a indicates a conveyor belt upon which articlesto be folded are carried through a folding machine,b indicates a portionof such an article.

As the latter is being carried forward, its leading edge engages and,moves an arm 0 which operates an electric switch d in series with anelectric switch e actuated by an arm f also adapted to be displaced bythe leading edge of the article b. Thereis a vertically movable plate gactuated by a solenoid hin the electric circuit containing the switchesd and e so that when both switches have been closed by the article bengaging and moving the same 0 and 1 respectively, the solenoid h raisesthe moV-.

ing plate gand the latter clips the leading edge of the article 1;against the fixed bar i as shown in Figure 3. A dashpot' j restrains thedownward movements of the moving plate g so as to ensure that the rearedge of the folded article b-has passed clear of the moving plate gbefore this again comes into contact with the conveyor a.

The, arm 1 is adapted torest on a projection k on the movingplate g sothat when the moving plate g rises to clip the article, it moves theforward end of the arm f backwards clear of the position in which thearticle is clipped ,betWeenthe-moving plate g and the bar i so thatjamming between the fixed bar 1', the article b and the is of wedgeshape to pick up the leading edge of the article so that it can belifted to clamp it against the bar i. The arm 1 rests on the top of thechannel and its lower end is raised rapidly when the moving plate rises.

Ordinarily when the article passes beyond the switch arm 0, the lattercauses its switch d to open which deenergizes the solenoid and allowsthe moving plate g to fall. Such plate may in certain cases fall soquickly that it traps the trailing edge of the article. To obviate this,we may arrange to stop the downward movement of the moving plate g bymeans of a catch which is released only when the folded article has beenconveyed beyond the folding mechanism. 1

Referring to Figures 4, 5 and 6, the moving plate g has a rearwardlyprojecting part m which can be engaged by the end it of a lever pivotedat p and connected by a link q to a solenoid r energized by electriccurrent obtained through a switch .r operated through a blade spring tfrom an arm a pivoted at v and having a cam shaped end w which engagesthe blade spring t. In Figure 4, the conveyor a is folding the article12, the leading edge of which is held between the moving plate g and thebar i. In Figure 5, the folded article has turned the arm u and throughits cam end w forced the blade spring I to close the switch s. Thisresults in the energizing of the solenoid r and in the end it of thelever 0 coming into a position to be engaged by the projection m on themoving plate g. In Figure 6, the moving plate g is shown held up by thelever 0. When the folded article passes beyond the arm u, the latterre-.

turns to its Figure 4 position. The switch s opens the circuitcontaining the solenoid r so that the latter is de-energized. The weightof the moving plate g then presses the lever 0 clear of the projectionin so that the moving plate falls on to the conveyor a.

We do not limit ourselves to the details of the mechanism for operatingthe catch lever o. For example, when the article 11 passes the arm 0 ofthe switch d, it may close the circuit of the solenoid r and suchcircuit will remain closed for a predetermined interval of time whichmay be for example two seconds during which the downward movement of themoving plate g will be arrested.

Figures 8 and 9 show a modification of the meansfor energising thesolenoid r of the arrangement illustrated in Figures 4, 5 and 6 tocontrol the catch 0 which holds up the descent of the moving plate guntil the folds of the article pass from beneath the moving plate. InFigures 8 and 9 a light sensitive cell 10 receives a beam of light froma light source 11 through the spaces between the narrowv belts whichmake up the conveyor a and when the cell 10 is energised, the solenoid ris in-- operative. When the folded article b comes between the lightsource 11 and the light sensitive cell 10, the solenoid ris energised,resulting in the end n of the lever 0 coming into the path of theprojection m on the moving plate g. The latter cannot therefore falluntil the folded article passes out of the beam of light from the lightsource 11, when the solenoid r will be de-energised and the moving platewill press the lever 0 clear of its path and fall on the conveyor a. V

In Figures 10 and 11, the lever o is actuated mechanically by the feelerarm 13 which when displaced by the folded article b causes the lever oto move from its out-o'f-service position in Figure 10 to its serviceposition in Figure 11. When the folded article b passe's'from beneaththe feeler arm 13, the lever 0 moves clear of the moving plate g.

We claim:

1. A folding machine comprising in combination a conveyor for thearticles to be folded, a first switch having an actuating arm soplacedw-ith regard to the conveyor that said first switch is closed bythe leading edge of an article passing over the conveyor, a secondswitch having an actuating arm so placed with regard to the conveyorthat said second switch is closed by the leading edge of said articlepassing over the conveyor subsequent to the closing of said firstswitch, a solenoid connected through both said switches, a platepositioned to receive 'said leading edge thereover and adapted to beraised by said solenoid when the article has closed both switches, astationary gripper bar arranged above said plate, so as to clamp saidleading edge against said plate said second switch actuating arm beingso located with respect to said plate that said actuating arm is movedupwardly and rearwardly by movement of said plate, and said secondswitch is held in closed position so long as said plate is raised.

2. The folding machine of claim 1 in which a dashpot is connected tosaid plate to restrain the rate of descent of the plate when released bysaid solenoid.

3. The folding machine of claim 1 in which a lateral projection ismounted on said moving plate and a catch is provided which is so locatedas to engage said projection to hold said plate in slightly raisedposition after release of said plate by said solenoid.

4. The folding machine of claim 3 in which said catch is brought intooperative position by a second solenoid energized through a switchoperated by the article being folded. I

5. A folding machine as claimed in claim 4, in which the first switchcloses the circuit to energize said second solenoid when the articlepasses from beneath the first switch arm, such circuit beingmaintainedfor a predetermined interval of time during which the articlepasses from beneath the moving plate.

6. A folding machine as claimed in claim 4, in which a third armoperated by the folded article beyond the second arm actuates a switchin the second solenoid circuit to energize the second solenoid and causethe catch to hold up the descent of the moving plate whilst the articleis beneath the third arm.

7. A folding machine as claimed in claim 4, in which the energization ofthe second solenoid is controlled by a light sensitive cell on to whicha beam of light is projected when the folded article comes into the pathof the beam at the delivery side of the moving plate, said secondsolenoid being energized and the catch made operative whilst the foldedarticle is obstructing the beam of light.

8. A folding machine as claimed in claim 3, in which the catch isconnected to a feeler arm which is displaced by the folded article atthe delivery side of the moving plate to render the catch operative toprevent the final descent of the moving plate.'

References Cited in the file .of this patent FOREIGN PATENTS

